Topics should be lowercase, even proper names, acronyms and initialisms (#346)

Author: garethsb

hooks/conan-center.py

@@ -720,6 +720,9 @@ def test(out):
                 if topic in invalid_topics:
                     out.warn("The topic '{}' is invalid and should be removed from topics "
                              "attribute.".format(topic))
+                if topic != topic.lower():
+                    out.warn("The topic '{}' is invalid; even names and acronyms should be formatted "
+                             "entirely in lowercase.".format(topic))
 
 
 @raise_if_error_output

tests/test_hooks/conan-center/test_invalid_topics.py

@@ -35,3 +35,11 @@ def test_invalid_topics(self):
         output = self.conan(['export', '.', 'name/version@user/channel'])
         self.assertIn("WARN: [INVALID TOPICS (KB-H064)] The topic 'conan' is invalid and should be"
                       " removed from topics attribute.", output)
+
+    def test_uppercase_topics(self):
+        tools.save('conanfile.py', content=self.conanfile.replace('"foobar",', '"foobar", "Baz", "QUX"'))
+        output = self.conan(['export', '.', 'name/version@user/channel'])
+        self.assertIn("WARN: [INVALID TOPICS (KB-H064)] The topic 'Baz' is invalid; even names "
+                      "and acronyms should be formatted entirely in lowercase.", output)
+        self.assertIn("WARN: [INVALID TOPICS (KB-H064)] The topic 'QUX' is invalid; even names "
+                      "and acronyms should be formatted entirely in lowercase.", output)